INS and type 2 diabetes mellitus: Furthermore, several epigenetic signatures, such as circulating microRNAs (miR-375 and miR-126) [61], differentially methylated circulating DNA in insulin gene promoter [62], and histone deacetylase 3 (HDAC3) inhibitors [63] have been proposed as novel tools for T2D diagnosis [61], prediction [62], and treatment [63], respectively.